Detection and Biocontrol of citrus nematode Tylenchulus semipenetrans in Wasit province

Abstract

This study had been conducted to detecte the existence of citrus nematode Tylenchulus semipenetrans in Wasit province, and to evaluate the effect of three biocontrol agents (T.harzianum, T.hamatum, Paecilomyces lilacinus) on larvae and eggs of this nematode in laboratory. The results of the existence of nematode in the areas of study shown significant variation between the studied areas and the highest population of larvae and females were recorded in Al-ssaouira district, where the number of larvae was 8.5 larva/250 g soil and 54.6 Female / 1 g of roots and the lower population was recorded in the AL-Muwafaqiya district which were 2.47 larva/250 g soil and 33.6 female/1g roots. The results also revealed that all bioagentsare effective in parasitizing the eggs and the more effective one is T.hamatum where the percent of parasitism was 85.49%. Field Experiment revealed the capacity of all tested fungi in reducing the population of nematode larvae in treated soil compared with non treated soil and the highest percent of reduction recorded in the case of Trichoderma harzianum which was 76.9% compared with the control 28.2%.